One-pot synthesis and photochemical diversification of pyrazolo[1,2-a]pyridazinones into 3D-rich scaffolds

Babnik, Ines (author), Petek, Nejc (author), Grošelj, Uroš (author), Svete, Jurij (author), Štefane, Bogdan (author)

We report a one-pot, three-component synthesis of pyrazolo[1,2-a]pyridazinones from tetrahydropyridazines, a transformation that was historically challenging due to competing ring contractions. The resulting compounds undergo photoinduced transformations, without the need for external photocatalysts, to afford diverse 3D-rich derivatives, including tricyclic cyclobutenes and γ-(pyrazol-1-yl)butanals. Enabled by mild conditions, this strategy offers an efficient, atom-economical route to structurally diverse pyrazolo[1,2-a]pyridazinones and their derivatives.

• Language: English
• Keywords: atmospheric chemistry, azomethine, cyclization, irradiation, reaction products
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: Str. 1563-1570
• Numbering: Vol. 91, iss. 4
• PID: 20.500.12556/RUL-179667
• UDC: 547.8:544.52
• ISSN on article: 0022-3263
• DOI: 10.1021/acs.joc.5c02313
• COBISS.SI-ID: 268035331
• Publication date in RUL: 19.02.2026

Record is a part of a journal

• Title: Journal of organic chemistry
• Shortened title: J. org. chem.
• Publisher: American Chemical Society.
• ISSN: 0022-3263
• COBISS.SI-ID: 235287

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: atmosferska kemija, azometin, ciklizacija, obsevanje, reakcijski produkti

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P1-0179-2020
• Name: Napredna organska sinteza in kataliza

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: I0-0022-2022
• Name: Mreža raziskovalnih infrastrukturnih centrov Univerze v Ljubljani (MRIC UL)